| /* |
| * tag.c - allocation/initialization/free routines for tag structs |
| * |
| * Copyright (C) 2001 Andreas Dilger |
| * Copyright (C) 2003 Theodore Ts'o |
| * |
| * %Begin-Header% |
| * This file may be redistributed under the terms of the |
| * GNU Lesser General Public License. |
| * %End-Header% |
| */ |
| |
| #include <stdlib.h> |
| #include <string.h> |
| #include <stdio.h> |
| |
| #include "blkidP.h" |
| |
| static blkid_tag blkid_new_tag(void) |
| { |
| blkid_tag tag; |
| |
| if (!(tag = (blkid_tag) calloc(1, sizeof(struct blkid_struct_tag)))) |
| return NULL; |
| |
| INIT_LIST_HEAD(&tag->bit_tags); |
| INIT_LIST_HEAD(&tag->bit_names); |
| |
| return tag; |
| } |
| |
| void blkid_free_tag(blkid_tag tag) |
| { |
| if (!tag) |
| return; |
| |
| DBG(DEBUG_TAG, printf(" freeing tag %s=%s\n", tag->bit_name, |
| tag->bit_val ? tag->bit_val : "(NULL)")); |
| DEB_DUMP_TAG(DEBUG_TAG, tag); |
| |
| list_del(&tag->bit_tags); /* list of tags for this device */ |
| list_del(&tag->bit_names); /* list of tags with this type */ |
| |
| if (tag->bit_name) |
| free(tag->bit_name); |
| if (tag->bit_val) |
| free(tag->bit_val); |
| |
| free(tag); |
| } |
| |
| /* |
| * Find the desired tag on a device. If value is NULL, then the |
| * first such tag is returned, otherwise return only exact tag if found. |
| */ |
| blkid_tag blkid_find_tag_dev(blkid_dev dev, const char *type) |
| { |
| struct list_head *p; |
| |
| if (!dev || !type) |
| return NULL; |
| |
| list_for_each(p, &dev->bid_tags) { |
| blkid_tag tmp = list_entry(p, struct blkid_struct_tag, |
| bit_tags); |
| |
| if (!strcmp(tmp->bit_name, type)) |
| return tmp; |
| } |
| return NULL; |
| } |
| |
| /* |
| * Find the desired tag type in the cache. |
| * We return the head tag for this tag type. |
| */ |
| static blkid_tag blkid_find_head_cache(blkid_cache cache, const char *type) |
| { |
| blkid_tag head = NULL, tmp; |
| struct list_head *p; |
| |
| if (!cache || !type) |
| return NULL; |
| |
| list_for_each(p, &cache->bic_tags) { |
| tmp = list_entry(p, struct blkid_struct_tag, bit_tags); |
| if (!strcmp(tmp->bit_name, type)) { |
| DBG(DEBUG_TAG, |
| printf(" found cache tag head %s\n", type)); |
| head = tmp; |
| break; |
| } |
| } |
| return head; |
| } |
| |
| /* |
| * Set a tag on an existing device. |
| * |
| * If value is NULL, then delete the tagsfrom the device. |
| */ |
| int blkid_set_tag(blkid_dev dev, const char *name, |
| const char *value, const int vlength) |
| { |
| blkid_tag t = 0, head = 0; |
| char *val = 0; |
| |
| if (!dev || !name) |
| return -BLKID_ERR_PARAM; |
| |
| if (!(val = blkid_strndup(value, vlength)) && value) |
| return -BLKID_ERR_MEM; |
| t = blkid_find_tag_dev(dev, name); |
| if (!value) { |
| if (t) |
| blkid_free_tag(t); |
| } else if (t) { |
| if (!strcmp(t->bit_val, val)) { |
| /* Same thing, exit */ |
| free(val); |
| return 0; |
| } |
| free(t->bit_val); |
| t->bit_val = val; |
| } else { |
| /* Existing tag not present, add to device */ |
| if (!(t = blkid_new_tag())) |
| goto errout; |
| t->bit_name = blkid_strdup(name); |
| t->bit_val = val; |
| t->bit_dev = dev; |
| |
| list_add_tail(&t->bit_tags, &dev->bid_tags); |
| |
| if (dev->bid_cache) { |
| head = blkid_find_head_cache(dev->bid_cache, |
| t->bit_name); |
| if (!head) { |
| head = blkid_new_tag(); |
| if (!head) |
| goto errout; |
| |
| DBG(DEBUG_TAG, |
| printf(" creating new cache tag head %s\n", name)); |
| head->bit_name = blkid_strdup(name); |
| if (!head->bit_name) |
| goto errout; |
| list_add_tail(&head->bit_tags, |
| &dev->bid_cache->bic_tags); |
| } |
| list_add_tail(&t->bit_names, &head->bit_names); |
| } |
| } |
| |
| /* Link common tags directly to the device struct */ |
| if (!strcmp(name, "TYPE")) |
| dev->bid_type = val; |
| else if (!strcmp(name, "LABEL")) |
| dev->bid_label = val; |
| else if (!strcmp(name, "UUID")) |
| dev->bid_uuid = val; |
| |
| if (dev->bid_cache) |
| dev->bid_cache->bic_flags |= BLKID_BIC_FL_CHANGED; |
| return 0; |
| |
| errout: |
| if (t) |
| blkid_free_tag(t); |
| else if (val) |
| free(val); |
| if (head) |
| blkid_free_tag(head); |
| return -BLKID_ERR_MEM; |
| } |
| |
| |
| /* |
| * Parse a "NAME=value" string. This is slightly different than |
| * parse_token, because that will end an unquoted value at a space, while |
| * this will assume that an unquoted value is the rest of the token (e.g. |
| * if we are passed an already quoted string from the command-line we don't |
| * have to both quote and escape quote so that the quotes make it to |
| * us). |
| * |
| * Returns 0 on success, and -1 on failure. |
| */ |
| int blkid_parse_tag_string(const char *token, char **ret_type, char **ret_val) |
| { |
| char *name, *value, *cp; |
| |
| DBG(DEBUG_TAG, printf("trying to parse '%s' as a tag\n", token)); |
| |
| if (!token || !(cp = strchr(token, '='))) |
| return -1; |
| |
| name = blkid_strdup(token); |
| if (!name) |
| return -1; |
| value = name + (cp - token); |
| *value++ = '\0'; |
| if (*value == '"' || *value == '\'') { |
| char c = *value++; |
| if (!(cp = strrchr(value, c))) |
| goto errout; /* missing closing quote */ |
| *cp = '\0'; |
| } |
| value = blkid_strdup(value); |
| if (!value) |
| goto errout; |
| |
| *ret_type = name; |
| *ret_val = value; |
| |
| return 0; |
| |
| errout: |
| free(name); |
| return -1; |
| } |
| |
| /* |
| * Tag iteration routines for the public libblkid interface. |
| * |
| * These routines do not expose the list.h implementation, which are a |
| * contamination of the namespace, and which force us to reveal far, far |
| * too much of our internal implemenation. I'm not convinced I want |
| * to keep list.h in the long term, anyway. It's fine for kernel |
| * programming, but performance is not the #1 priority for this |
| * library, and I really don't like the tradeoff of type-safety for |
| * performance for this application. [tytso:20030125.2007EST] |
| */ |
| |
| /* |
| * This series of functions iterate over all tags in a device |
| */ |
| #define TAG_ITERATE_MAGIC 0x01a5284c |
| |
| struct blkid_struct_tag_iterate { |
| int magic; |
| blkid_dev dev; |
| struct list_head *p; |
| }; |
| |
| extern blkid_tag_iterate blkid_tag_iterate_begin(blkid_dev dev) |
| { |
| blkid_tag_iterate iter; |
| |
| iter = malloc(sizeof(struct blkid_struct_tag_iterate)); |
| if (iter) { |
| iter->magic = TAG_ITERATE_MAGIC; |
| iter->dev = dev; |
| iter->p = dev->bid_tags.next; |
| } |
| return (iter); |
| } |
| |
| /* |
| * Return 0 on success, -1 on error |
| */ |
| extern int blkid_tag_next(blkid_tag_iterate iter, |
| const char **type, const char **value) |
| { |
| blkid_tag tag; |
| |
| *type = 0; |
| *value = 0; |
| if (!iter || iter->magic != TAG_ITERATE_MAGIC || |
| iter->p == &iter->dev->bid_tags) |
| return -1; |
| tag = list_entry(iter->p, struct blkid_struct_tag, bit_tags); |
| *type = tag->bit_name; |
| *value = tag->bit_val; |
| iter->p = iter->p->next; |
| return 0; |
| } |
| |
| extern void blkid_tag_iterate_end(blkid_tag_iterate iter) |
| { |
| if (!iter || iter->magic != TAG_ITERATE_MAGIC) |
| return; |
| iter->magic = 0; |
| free(iter); |
| } |
| |
| /* |
| * This function returns a device which matches a particular |
| * type/value pair. If there is more than one device that matches the |
| * search specification, it returns the one with the highest priority |
| * value. This allows us to give preference to EVMS or LVM devices. |
| * |
| * XXX there should also be an interface which uses an iterator so we |
| * can get all of the devices which match a type/value search parameter. |
| */ |
| extern blkid_dev blkid_find_dev_with_tag(blkid_cache cache, |
| const char *type, |
| const char *value) |
| { |
| blkid_tag head; |
| blkid_dev dev; |
| int pri; |
| struct list_head *p; |
| |
| if (!cache || !type || !value) |
| return NULL; |
| |
| blkid_read_cache(cache); |
| |
| DBG(DEBUG_TAG, printf("looking for %s=%s in cache\n", type, value)); |
| |
| try_again: |
| pri = -1; |
| dev = 0; |
| head = blkid_find_head_cache(cache, type); |
| |
| if (head) { |
| list_for_each(p, &head->bit_names) { |
| blkid_tag tmp = list_entry(p, struct blkid_struct_tag, |
| bit_names); |
| |
| if (!strcmp(tmp->bit_val, value) && |
| tmp->bit_dev->bid_pri > pri) { |
| dev = tmp->bit_dev; |
| pri = dev->bid_pri; |
| } |
| } |
| } |
| if (dev && !(dev->bid_flags & BLKID_BID_FL_VERIFIED)) { |
| dev = blkid_verify_devname(cache, dev); |
| if (dev && (dev->bid_flags & BLKID_BID_FL_VERIFIED)) |
| goto try_again; |
| } |
| |
| if (!dev && !(cache->bic_flags & BLKID_BIC_FL_PROBED)) { |
| if (blkid_probe_all(cache) < 0) |
| return NULL; |
| goto try_again; |
| } |
| return dev; |
| } |